The present invention relates to containers, and particularly to plastic containers capable of withstanding high internal or external pressures both in the axial direction as well as in the radial direction.
Containers (which expression also includes vessels, housings, tanks, etc.), particularly large constructions useful for containing liquids or gasses under high pressure, are at the present time usually built of metal and/or laminated composite materials because of the high resistance required in order to withstand high axial and radial pressures. Containers made of metal are very time-consuming and costly to build because of the need first to produce the various components of the container and then to assemble them together, e.g., by welding. Moreover, a high degree of expertise is required because if the welding (or other bonding technique) used for assembling the components together is not perfectly executed, leaks may develop during the use of the container. Further, metal containers tend to corrode, oxidize, pit or develop unpleasant odours or tastes, unless non-corrosive metals are used, such as stainless steel, or protective layers or coatings are applied, both of which substantially increase the expense and/or time in producing the containers. Building containers made from laminated composite materials is also time- C consuming, expensive and expertise-dependent because of the need to manufacture the components and then assemble them together.